Combustion-arrester for moving-picture machines



R, J. KOEPP.

COMBUSTION ARRESTER FOR MOVING PICTURE MACHINES.

APPLICATlON FILED SEPT. I. 1920.

1,379,449. Patented May 24,1921.

unnnnuununnnnnunnu a citizen of the United States, residing at UNITED STATES PATENT ol-"ncn nnmnsnr .1. KOEIP, or CLEVELAND, onto.

GONfIBUSTION- ARRESTER FOR MOVING-PICTURE MACHINES.

Specificationof Letters Patent. Patented 24 1921 Application filed September 1, 1920. Serial No. 407,519. 1

To all whom it may concern:

Be it known that I, REINHART J. KOEPP,

Cleveland, in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Combustion-Arresters for Moving-Picture Machines, of which the following is a full, clear, and

' exact description, reference being had to the accompanying drawlngs. I This invention relates to combustion arresters for moving picture machines and similar machines used for projecting pictures by means of concentrated light rays.

The object of my invention is to construct a film guide that may be maintained in close proximity to the sensitized surfaces of the film without scratching or marring the same.

Another object of the present invention is to restrict the opening through which the film passes by'means of a diaphragm that likewise acts as a flame shield and which also acts as a combustion arrester.

An embodiment of my invention, is set forth in the drawings and is hereinafter more fully "described in reference to the same, and the essential features of the invention are set out in the claims.

In using a high powered light for pro jecting pictures from transparent films, a break often occurs at someplace in the film with a consequent stopping of the machine and if the projecting light is concentrated on a section of the film for any appreciable K length of time a local ignition of the film will take place.

Various means have been devised in the past for preventing the explosion of these highly inflammable films, but I have found that the possibilities of explosion, and of consequent fire and panic are still present when man of these so-called safety devices are place upon projection machines, and also that they impede the efliclent use of the machine.

I have found, also, that by confining the film to a space approximately equal to the thickness of its transverse cross-section as it approaches and leaves the projecting aperture by means of a yielding diaphragm, it is possible to decrease the rate of combustion and to finall arrest it.

Referring to t e drawings, in Figure 1, I have shown a cross-section of a film guide such as is used on the standard projection machines, in combination with my attachmachine. 17 is secured to the shutter support 12 ment, while Fig. 2 shows a vertical elevation of the same mechanism as seen from the light pro ecting side of the machine. In Fig. 8,

'Ihave shown a perspective view of an ordiof the film the other side, of which slides onthe back guide plate 8 which is suitably supported on the projection machine, and in which there is a rectangular projecting aperture 6. A shutter 10 is pivotally mounted at l-lon the spring and shutter support 12,

in which a rectangular aperture 13 is also provided for the passage of the projecting rays 14:. The gate 15 is pivotally supported at 16 and .may be moved about this pivot to expose the back guideplate 8 and incidentally to start a new or parted film through the One end of a bifurcated spring through an opening 21, while the bifurcated ends rest upon the curved ends of the leaf springs 18 which in turn bear upon the flanged portions 20 of the film guide legs 22 and hold the guide rails 24: in sliding contact with the edges of the film. The amount of pressure of the springs may be adjusted bymeans of the screw 19 so that the rails 24 will bear upon the film with sufficient pressure to always maintain the moving film in a plane substantially normal to the path of the light rays. On the gate 15a latch 23 is mounted and is adapted to hold the gate in the closed position shown in Fig. 1 and against the force of springs 18 which would otherwise force it open.

'A ide spool26 is shown mounted on and at the top of the gate and serves to guide the film to the projecting apertures I as it passes from the reel.

I have found that the'area provided for the passage of the film which is inclosed by I the guide rails 24, Fig. 3, connecting portion 25 and back guide plate 8 is so large that a flame starting at the projecting aperture will travel alon the film and eventually explode the ree and I have further found that by restricting this area by means of a diaphragm such as I have shown in Fig. 4 to approximately the area of the crosssection of the film I can confine the combustion to a section of the film corresponding in area to the area of the projecting aperture.

The diaphragm has sloping portions 28, the width of which is equal to the distance between the guide rails 24, and a rectangu lar extension 29 which is of suflicient length to extend part way through the aperture 13 when the diaphragm is mounted on the guide plate 7 In order to prevent the diaphragm from scratching or marring the film as it passes through the guides the surfaces of the portions 28 may be highly polished and as a further means of preventing a damaging of the moving film, the diaphragm may be secured to the guide plate at one end 31 only, while the other end may be free to adjust itself on the surface of the portion 25 of the guide plate. As the gate 15 is closed on the film the edges 32 and 33 are maintained in yielding contact with the surface of the film. I

It is to be seen that if the operator does not close the shutter 10 immediatel upon the stopping of a section of the fi m, the film becomes overheated at the projection aperture and ignites but the combustion will be limited to an area on the film corre sponding to the area inclosed by the diaphragm edges 32 and 33 as shown in Fig. 4: and the flame resulting from this local combustion is guided away from the film. By limiting the burnt area of the film as shown in Fig. 6, a suflicient section remains whereby a continuation of the film through the machine may be effected without delaying to mend the same.

It is evident that by the utilization of my invention the possibilities of fire are greatly lessened and that the loss of life through panic is prevented. It is also evident that no obstruction or interferences are encountered when adapting my invention to any of the standard makes of projection machines, for it is simple and compact and at the. same time efficient.

Furthermore my invention will arrest combustion in such a manner'that' the continuity of the film is not destroyed and incidentally the time lost that is expended in mending damaged films during the projecting of the same will be eliminated.

Having thus described my invention, what I claim is: i

l 1. The combination with a film projecting means, of a flame'arrester comprisinga box having open ends and adapted to surround the projection rays, the inner end of the box being adjacent the film, and a pair of flaps at the inner end of the box extending therefrom'adjacent to and longitudinal of the film, L

2. The combination with a film projecting means, of a flame arrester adapted to stand adjacent the film, and comprising a rectanyieldably maintained in contact with the v 4. The combination with film projecting means, of a flame 'arrester comprising a sheet metal rectangular box having resilient sheet metal flaps extending upwardly and downwardly from its top and bottom edges which are adjacent the film. i

5. As an article of manufacture a combustion arrester for picture projecting films, comprising a flexible diaphragm adapted to be secured to a picture projecting machine, said diaphragm having a projecting aperture surrounded by a flame guiding means Edapted to direct the flame away from the 6. As an article of manufacture, a combustion and flame arrester, comprising a yieldable diaphragm in which a projecting aperture is provided, said aperture being surrounded by extensions from the diaphragm and normal to the plane of the aper ture, said extensions constituting a flame guide adapted to lead the flame away from the film.

7. As an article of manufacture a combustion and flame arrester comprising a substantiallyrectangular box-like structure with open ends adapted to surround the projection rays in a moving picture machine and having two integral, resilient flaps on one open end of the box, said flaps being inclined toward the other end of the box, each flap being co-extensive with the side to which it is attached and one of which is adapted to be secured to the film guide of said picture machine, whereby both flaps may yieldingly maintain the ends of the walls of the box in contact with the moving film in'the machine.

.8. The combination with means for guiding a film, of a flame arrester comprising an open ended box having flaps extending upwardly and downwardly from its inner upper and lower edges, respectively, and spring means pressing the arrester toward the film.

9.- The combination with film projecting means, of a flame arrester having an open ended rectangular box with flaps extending upwardly and downwardly from one upper and lower edge respectively, means for positioning said arrester adjacent the film, and a pair of leaf springs on opposite sides of said box for pressing the arrester toward the film,

10. In a motion picture machine, the combination with a film guiding plate, of a member spring pressed toward the film, and having a light opening, and wings at its opposite sides, springs engaging said wings to press the member toward the film, and a flame arrester having an open ended box extending through said light opening, and flaps carried by the box at its top and bottom edges between said member and guide plate and extending upwardly and downwardly, respectively.

11. In a motion picture machine, the combination with film guiding plate having a light opening, a movable member having a registering light opening, means for pressing the movable member toward the film guiding plate, and a flame arrester having an open ended box portion occupying the opening in the movable member and having flaps extending upwardly and downwardly between the movable member and plate.

12. In a motion picture machine, the combination of a film guiding plate having a light opening, a pressing and guiding device having a light opening registering with the opening in the plate, means for press ing the guiding member toward the plate, said guiding member having parallel ribs adapted to engage the film, and a flame ar rester having an open ended metallic box portion adapted to surround the picture rays and occupy the opening in the spring pressed guide and having metallic flaps ex tending upwardly and downwardly, respectively, from one top and bottom edge of the box, said flaps lying between the plate and the spring pressed member and between the two guiding ribs on the latter.

In testimony whereof, I hereunto afiix my signature.

REINHART J. KOEPP. 

